The pdf format itself. Imagine a 'normal' pdf at a page size of A4, Acrobat Reader (AR) on the PPC renders it the same way as AR on the PC. You would have to zoom in and scroll from left to right to read a sentence, up and down to read the page, zoom in, zoom out, etc. Nott very handy for reading a book. The solution is to Tag a pdf, but this makes the pdf much larger, and space on a pda is at a premium (these days a little less so with the advent of 256MB+ cards).
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So i checked how much bigger those files would get, and it seems i made a boo-boo. I used Cry Havoc (7.23MB), i tagged it in Acrobat 6 Pro and it turned out into a 7.37MB file, not that much larger at all. I find this strange, in the past i tried this with a different file and the document turned out three times as big, maybe it was because i was an old version of Acrobat (5 i believe). A zipped txt file is still a lot smaller...
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Even then it's not optimal reading, mostly because images tend to be far to large, navigation tools in the PPC reader aren't up to spec, etc.
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Navigation still suck though, even when using reflow, text is largely unreadible, only after pressing zoom about a dozen times it will become vaguely readible...
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